1. Technical Field
The invention generally relates to lenses and lens barrels for use with miniature cameras.
2. Related Art
Various personal electronic devices are often implemented with miniature cameras. Such cameras may include, for example, a lens barrel assembly that includes a lens barrel with one or more lenses that pass light to an image capture device, such as an image sensor. However, as ever-smaller personal electronic devices are produced, the size of their corresponding miniature cameras must be reduced. Unfortunately, existing lens barrels and their associated lenses can be a limiting factor in reducing the size of such cameras.
For example, certain conventional lens barrels may fully enclose all lenses of a miniature camera. Such implementations require a corresponding minimum lens barrel size that is sufficient to surround all of the lenses. Conventional lens barrels may also be implemented with a uniform diameter corresponding to the diameter of the largest lens of the camera. Such designs fail to efficiently utilize the limited space available in applications utilizing miniature cameras.
Lens barrel configurations can also impact the size of lenses which may be used in miniature cameras. For example, lenses may be inserted into conventional cylindrical lens barrels by tools configured to grip the outer surfaces of the lenses. However, in order to permit insertion of such lenses into a conventional cylindrical lens barrel, the lenses may be implemented with a useable diameter that is smaller than the interior diameter of the lens barrel. This smaller diameter provides clearance between the lens and the interior surfaces of the lens barrel to permit insertion of a lens gripping tool while a lens is inserted into the lens barrel. Alternatively, such lenses may be implemented with flattened external surfaces to provide sufficient clearance for such tools. In each of these cases, the useable diameter of the lens will be reduced without a corresponding reduction in the overall size of the lens barrel assembly.
In addition, lenses produced by injection molding manufacturing processes typically include gate vestiges which remain part of the lens. In order to permit insertion of these lenses into conventional cylindrical lens barrels, the lenses may be manufactured to include such gate vestiges within the diameter of the lens. However, in such implementations, the useable diameter of the lens will be reduced to include only the remaining interior diameter of the lens that does not include the gate vestige. Similar to techniques described above, the useable diameter of the lens will be reduced without a corresponding reduction in the size of the lens barrel assembly.